Permanent moulds



Aug. 20, 1963 A. VAYDA 3,100,919

' PERMANENT MOULDS Filed July 6. 1960' 3, Sheets-Sheet 1 INVENTOR i fl/euwdre. V 9

's ATTORNEY.

Aug. 20, 1963 VAYDA PERMANENT MOULDS 3 Sheets-Sheet 2 Filed July 6, 1960 INVENTOR.

y 4 I mm Vay 3 ATTORNEY Aug. 20, 1963 A. VAYDA 3,100,919

PERMANENT MouLDs Filed July 6, 1960 a Sheets-Sheet 5 BY M. %MM4 M3 ATTORNEY,

United States Patent 3,100,919 PERMANENT MQULDS Alexandre Vayda, Paris, France, assignor to Fcnderite Societe a Responsabiiite Limitee, Paris, France Filed .lnly 6, 1969, Ser. No. 41,102 Claims priority, application France July 7, 1955 2 Claims. (U. 22----9) This invention relates to a method of providing a permanent mould or the like with an exothermic lining, as well as to a form which is suitable for performing the method.

When steel has been poured into a permanent mould or into a casting fiask and the casting solidifies it is known that the dissipation of heat through the walls can be reduced if the mould or the like is provided with an exothermic lining and that the formation of pipes by shrinkage in the head of the casting can thus be prevented. It is also known that the lining may consist of a combination of an exothermic product with a binding agent such as water glass. Such a mixture will set when carbon dioxide gas is blown into the same.

In the past exothermic linings in the head of the permanent mould were provided by using a pie-formed lining elements consisting of exothermic mixtures. These were affixed to the walls of the mould adhesively or by some other means. This was a tedious procedure and it is also difiicult to perform. The location of the elements often caused very considerable trouble.

It is the object of the present invention to overcome these defects and to provide useful means which will permit linings of exothermic mixtures to be directly applied to the inside walls of permanent moulds and the like.

The invention therefore relates to a form for providing the interior of a permanent mould with an exothermic lin-' ing. The form proposed for this purpose comprises a plurality of elements which together form a continuous wall inside the permanent mould, sealing means at the lower edge of the wall elements of the form, a central frame connected with vertically adjustable bearing arms for suspending the form in the permanent mould, an admission system for supplying a hardening medium through the wall elements of the form to the exothermic lining, and supporting bars connected with the wall elements for withdrawing the form from the lining when this has set.

According to a particular embodiment the bars which support the elements of the wall of the form are fitted at their ends with racks for engagement of one or more pinions mounted on a central actuating shaft. These rackended bars may be guided in appropriate sleeves which are affixed to the rigid central frame of the form. The pinions may be operable by hand or by means of a motor, and the later may, for instance, be mounted on the central frame.

If desired, control may be completely automatic and, for instance, an electronic control system may be provided for switching the motor on and 0E at the proper times. However, it will be readily understood that the rigid central frame may be used to support drive means of some alternative kind.

If a motor is used for moving the wall members of the form, then this motor may at the same time serve for operating a vibrator (shaker) which may likewise be mounted on the rigid central frame, and used to consolidate the exothermic mixture which fills the cavity between the mould and the form.

The walls of the form may consist of simple or compound elements which face the lateral walls of the mould, and of arched wing members constituting the corners. In a preferred embodiment of the form each such wing member may be hingeably aifixed to the vertical edge of one of the adjacent wall members, whereas the other edge is adapted to pass slidably through guide means on the edge "ice of the other adjacent wall member. This arrangement will ensure the formation of an unbroken surface irrespectively of the relative position of the wall members, thus making the form automatically adaptable to moulds which dimensionally differ by small amounts. The profile of the arched wing member is determined by the nature of the guide means employed. For instance, guide rollers may be provided on the edge of the adjacent wall member in such manner that a gap of suitable width is left between the rollers and the edge of the wall member.

The invention can thus be embodied in numerous forms of construction all of which comply with the principles upon which the invention is based. Several forms of construction of a form according to the invention will be hereafter described with reference to the accompanying drawings, and further features will be revealed which are likewise of some importance to the invention. Moreover, although the following examples relate to the application of the invention to a permanent mould, this fact is by no means intended to limit the scope of the present invention which may also be used for the purpose of providing exothermic linings, for instance, in flasks and casting boxes in foundries.

In the drawings:

FIG. 1 is a plan view of a permanent mould with a form according to the invention inserted therein;

FIG. 2 is a fragmentary section of FIG. 1, illustrating the arrangements for guiding the wing portions constituting the corners of the form, shown on a larger scale;

FIGS. 3 and 4 illustrate a form according to the invention equipped with angled wall elements, with means for the elevational adjustment thereof and with a covered internal cavity, in sections on the lines 3-3 and 44 in FIGS. 4 and 3, respectively;

FIG. 5 is a plane section on lines 5-5 in FIG. 3.

In the form of construction illustrated in FIG. 1 the form comprises a rigid central frame 10 consisting of tubular guide members 11 and cross bracing struts 12. The form as such consists of wall elements 13 and 14 facing the inside walls of the mould 15. Elements 13 on the longer sides of the mould are fitted with rods 16 which slidably engage the ends of the tubular guide members 11 of the above-described frame. The frame It is connected with vertically adjustable bearing arms 55 by rods fixed to the guide members 11.

The wall elements 13 and 14 are each provided with racking arms '17 which are slidably mounted on the tubular members 11 and the cross bracing struts 12, and which at their ends are fitted with racks r18 engaged by a pinion 19 adapted to be rotated either by hand or by an electric motor secured to frame 10. The wall of the form is completed by arched wing members 20 which constitute the corner portions of the form and which are connected with the elements 14 of the side walls by hinges 21, the deflectable ends of said wing portions being slidably engaged by guide means 22 provided at each end of the wall elements 13.

The wall elements of the form are of hollow construction and the inside shell which faces the cavity 28 which is to be filled with the lining material is provided with a plurality of regularly distributed holes 29 for supplying hardening medium to the exothermic lining. The shell 3%) of the form which faces the interior of the mould is provided with one or several connections for pipes 32 through which the hardening medium can be admitted from a distributor 33. A sealing flange 34 delimits the bottom end of the cavity for the reception of the exothermic lining, said flange being lipped with a strip of leather, rubber, or like elastic material which makes a suitably tight joint with the inside of the wall of the mould 15.

r The guide means 22 mentioned above are formed by the bevelled conformation 23 of the lateral edges of wall elements 13 and cooperating rollers 24 mounted on arms 25 secured to the wall elements 13 in such manner that a gap 26 remains between said rollers and the bevelled edges 23 for the slida-ble insertion of the ends of the wing portions 20. The described arrangement ensures that the wing portions and the adjacent lateral wall elements 14 of the form will form an unbroken surface in any position of adjustment of the form.

FIG. 2 shows the construction of the slidable joint between the corner portion 20 and the adjacent lateral wall portion of the form in greater detail. The drawing in dotted lines illustrates the positions of the wall elements of the form when this is contracted preparatorily to being inserted into'the permanent mould, whereas the full line drawing illustrates the position of the same elements after they have been expanded by rotation of pinion H in the direction of arrow F (FIG. 1) into the required position in relation to the walls of the permanent mould 15.

It will be at once understood that the described arrangement for guiding the arched wing members 2h will readily permit the size of the form to be adjusted to different moulds which differ to some extent in their internal dimensions. The profile of the arched wing members is adapted to slide smoothly through the guide means.

FIGS. 3 and 4 illustrate a form according to the invention which is equipped with special means for vertically adjusting the form relative to bearing arms 55. These means permit the required lining to be applied to the inside of a mould at any level in accordance with the charge of cast material the mould is to contain. To this end an actuating shaft 42 is provided which is mounted in a central sleeve 54 and serves for raising and lowering the walls of the form relative to the bearing arms 55. The upper end of the shaft carries a handwheel 57. The bottom end of the shaft which carries a pinion 41 is mounted in a lower frame plate 44 which carries guide sleeves 43 for racks 44 which are the ends of supporting bars 39 for the wall elements and which engage with said pinion 41. The lower end of the sleeve 54 which carries the actuating shaft 42 is connected with the lower frame plate 44 by means of an upper frame plate 53 and uprights 45. The outside of the sleeve 54- is formed with a rack 56 engaged by a lifting pinion 57'. This lifting pinion is mounted in a tube 58 which is rigidly connected with hearing arms 55 placed across the top of the mould, and which also serves to guide the sleeve 54. Since the actuating shaft -42 is rotatable in sleeve 54 but not slida-bly dis-placeable therein, rotation of the shaft 59 which carries the lifting pinion 57' will permit sleeve 54 including actuating shaft 421 to be raised and lowered in relation to the edge of the permanent mould. The parts connected with the sleeve, more particularly the wall elements of the form can thus be elevationally adjusted as desired inside the. mould. Above the upper end of sleeve 54 the actuating shaft 42 carries a disc-shaped member '60 which is fitted with arresting means 61 for cooperation with the upper flanged edge 62 of sleeve 54. When the two members 60 and 62 are locked together shaft 42 cannot be rotated and the wall elements of the form will thus be locked in their adjusted position. By this or by some equivalent mechanism the form can be located in the required position, especially in its working position before the exothermic mixture is introduced. If desired, a crane could be used to adjust the vertical level of the form and special adjusting means of the afore-described kind might there be dispensed with.

In order to facilitate introducing the mixture into the .cavity or gap 28 provided for the reception thereof the embodiment of the invention illustrated in FIGS. 3, 4 and is provided with a cover 63 which closes the space inside the walls of the form. This cover is divided into several sections which are secured to the associated wall elements of the form, thus permitting the wall portions together with the sections of the cover to be freely withdrawn from the inside wall of the mould. The centre of the cover 63 has an opening 64 for the passage therethrough of the sleeve 54 and of the actuating shaft 42. In order to prevent any of the mixture from accidentally dropping into this hole 64, the latter provided with a collar 65 secured, on the one hand, to the cover 63 and, on the other, to the tube 53 which slidably guides sleeve 5d. The provision of the cover permits a predetermined quantity of the exothermic mixture to be poured into the top of the permanent mould without particular care, because any part of the mixture which drops on the cover can be subsequently easily pushed into the cavity 28 between the fornr and the mould. Another possible form of construction is to provide the cover with an appropriate outward slope in such manner that the mixture will of itself slide off the cover into the cavity without being specially encouraged to do so.

The section according to FIG. 5 shows the wall of the form consisting of angularly bent wall elements 3'5 to 33 whichadjoin approximately in the centres of the sides of the mould and overlap in such manner that each wall element either overlaps or underlaps the ends of both the adjacent wall elements. Each of the wall elements is connected with a supporting bar 39 which terminatesin a rack portion 49. The bars and racks associated with the several wall elements extend approximately diagonally towards the centre of the form in such a way that all four racks are engageable by the pinion 41 mounted on the central actuating shaft 42. The racks 44 on the several bars 39 move in the guide sleeves 43 which are secured to the lower frame plate 44 connected by the uprights 45 with the upper frame plate. The two sleeves which guide a pair of parallel racks are located in the same plane, whereas the two sleeves associated with the other pair of racks are arranged to cross over the first pair of sleeves underneath.

The hardening medium is supplied to the individual wall elements through flexible tubes 46 connected with T-junctions 47, 48 which communicate with a central admission pipe 49 extending alongside the central actuating shaft 42. Conveniently a stop cock and heating means not shown may be provided in the medium admission system in front of the branch connections, in order to facilitate control. Moreover, an automatic time-controlled valve may be incorporated in the supply line for cutting off the supply of medium at the end of a predetermined period of hardening. The individual lengths of flexible pipe supply associated elements of the wall of the form through an appropriate distribution system 50 which comprises a plurality of branches 51 for discharging the medium through a plurality of openings in the form wall. Small plates 52 cover these outlets on the side facing the wall of the mould. These plates are perforated by a large number of ducts which diverge outwardly and thus ensure a particularly efiective distribution of the hardening medium.

I claim:

1. A form for providing the interior of a permanent steel casting mould with an exothermic lining, comprising a central farme, a plurality of wall elements which to gether form a continuous wall inside the permanent mould supported by said central frame, sealing means at the lower edge of the wall elements of the form including a flange projecting outwardly towards the mould wall, arms supported by the mould and supporting said central frame thereby suspending the form in the permanent mould, an admission system for supplying a hardening medium through the wall elements of the form to the exothermic lining, one supporting bar for each wall element movably connected to said frame and rigidly carrying the wall element, the bars being disposed at an angle to the respective mould walls and operable to position said wall eic- 'ments for the lining operation and, respectively, to rertraot them for withdrawing the form from the set lining, control means connected to said frame and operable for moving said supporting bars to position and to retract the Wall elements, said admission system comprising said wall elements defining adjacent the wall chambers having perforations, a central pipe operative to be connected to a source of carbon dioxide, and branch pipes extending from the central pipe to the several chambers of the wall elements for supplying carbon dioxide to the chambers to be expelled through the perforations thereof.

2. A form, as claimed in claim 1, said frame comprising a sleeve member for each of the supporting bars, said control means comprising a central shaft mounted on said frame and including a pinion, said bans terminating in 6 rack portions engaging the pinions on said central shaft and being aotuatable thereby and being guided in said sleeve members.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A FORM FOR PROVIDING THE INTERIOR OF A PERMANENT STEEL CASING MOULD WITH AN EXOTHERMIC LINING, COMPRISING A CENTRAL FRAME, A PLURALITY OF WALL ELEMENTS WHICH TOGETHER FORM A CONTINUOUS WALL INSIDE THE PERMANENT MOULD SUPPORTED BY SAID CENTRAL FRAME, SEALING MEANS AT THE LOWER EDGE OF THE WALL ELEMENTS OF THE FORM INCLUDING A FLANGE PROJECTING OUTWARDLY TOWARDS THE MOULD WALL, ARMS SUPPORTED BY THE MOULD AND SUPPORTING SAID CENTRAL FRAME THEREBY SUSPENDING THE FORM IN THE PERMANENT MOULD, AN ADMISSION SYSTEM FOR SUPPLYING A HARDENING MEDIUM THROUGH THE WALL ELEMENTS OF THE FORM TO THE EXOTHERMIC LINING, ONE SUPPORTING BAR FOR EACH WALL ELEMENT MOVABLY CONNECTED TO SAID FRAME AND RIGIDLY CARRYING THE WALL ELEMENT, THE BARS BEING DISPOSED AT AN ANGLE TO THE RESPEC- 